If you create Tx3, in which you spend all inputs of Tx2 and the change input of Tx1, then you make it clear that the owner of Tx2's and Tx1's inputs is the same.
It is surprising, how often such transaction is marked as a CoinJoin transaction. There was even a case, when people thought that another bitcointalk user did it. Also, it is surprising, how often people think that the round amount is the payment, many services did it wrong, and thought that 14 was a payment, and 5.99 was a change, where in practice, there is a higher chance to see prices like 5.99 in many shops (because of that .99 ending that has a psychological impact on many customers).
Before making Tx3, spectators can assume that you sent money to somebody else, but the moment you publish Tx3, they can be sure that this isn't the case.
So far, I can't find a single page that tracked my UTXOs correctly. For example, blockchair always did it wrong. It was funny they assigned low or critical privacy score, and then gave a totally wrong results about what really happened.
Yeah, this doesn't work at all. You can split up an UTXO as many time as you want, but as soon as you use multiple inputs together in one transaction, then all those inputs are linked together as most probably belonging to the same entity. If all those inputs can be traced back to the same entity in the last 5 or 10 parent transactions, then you've achieved absolutely nothing except wasting money on fees.
By following that logic, someone can conclude that all LN channels on Taproot addresses are always owned by a single person. Because if you combine deniability and Taproot, then you don't know, how many parties there are. Also note that the same trick can be used on legacy addresses to some extent, because of homomorphic encryption:
https://duo.com/labs/tech-notes/2p-ecdsa-explainedSo, how do you know that Tx1 is not a channel opening transaction, Tx2 is not a channel closing transaction, and Tx3 is not owned by someone else, who received coins after swap? Also, for some LN wallets, this is the default, for example when you open a channel in the Phoenix wallet, then after going on-chain, your channel will stay opened, and you will receive completely different coins from a swap.
More examples:
https://www.truthcoin.info/blog/deniability/#c-example